Build vs Buy Integration: The True Cost of Custom ERP & Ecommerce Integrations

Why “owning the code” often costs more than you expect

When organisations evaluate integration options between their ERP, ecommerce platforms, marketplaces and internal systems, a familiar argument often emerges:

Why should we pay a monthly integration fee when we can build it ourselves once and own it?

On the surface, the logic feels sound. A once-off capital investment appears easier to justify than an ongoing operating expense. Ownership sounds attractive. Control feels reassuring.

But in practice, companies that choose to build their own integrations almost always underestimate the true, long-term cost — financially, operationally and strategically.

Integrations are not static assets. They are living systems that require continuous maintenance, specialist expertise and ongoing adaptation as your business, volumes and technology stack evolve. When these realities are fully accounted for, the economics often favour using a proven integration platform like Stock2Shop.

What is the true cost of building your own integration?

The true cost of building a custom integration includes not only the initial development effort, but also ongoing maintenance, dependency on scarce technical skills, opportunity cost for internal teams, and the risk of rebuilding when systems or platforms change. Over a 3–5 year period, these costs often exceed the predictable monthly cost of a managed integration platform.

The Hidden Costs of Building Your Own Integration

1. Initial build costs are only the starting line

Custom integrations rarely stop at “just connecting systems”.

Even a basic ERP-to-ecommerce integration typically requires:

• Solution architecture and technical design
• Custom development and testing
• Error handling, logging and monitoring
• Security, authentication and permissions management
• Documentation, training and handover

What begins as a “simple sync” often becomes a multi-month project, whether built internally or outsourced. These costs are usually capitalised — but they represent only the first phase of the integration’s lifecycle.

2. Ongoing maintenance is not optional

Once an integration goes live, maintenance starts immediately.

Common triggers include:

• ERP upgrades and patches
  When ERP APIs or data structures change, custom integrations often need to be modified or rewritten.
• Ecommerce platform updates
  Platforms like Shopify, WooCommerce and Magento release frequent updates that can introduce breaking changes.
• Bug fixes and exception handling
  Edge cases typically only appear under real trading conditions.
• Performance and scalability requirements
  As order volumes increase, custom integrations often require refactoring to maintain performance.

Each of these creates ongoing technical cost and delivery risk.

3. Dependency on Scarce Technical Skills

Custom integrations concentrate knowledge in people, not systems.

Over time, organisations become dependent on:

• Internal developers who eventually move on
• External consultants whose contracts end
• Poorly documented code that becomes difficult to maintain

When key individuals leave, undocumented integrations become expensive — or impossible — to maintain. Replacing this knowledge often costs more than the original build.

By contrast, specialised integration providers retain institutional knowledge across multiple customers, ERP systems and ecommerce platforms, reducing reliance on individual contributors.

4. Opportunity Cost for Your IT Team

Every hour spent maintaining bespoke integrations is an hour not spent on:

• Strategic initiatives
• Customer experience improvements
• Data and analytics projects
• Innovation and competitive differentiation

Integration infrastructure rarely differentiates a business, yet it consumes a disproportionate share of technical time when managed internally.

5. Overcapitalising on a Short-Lived Asset

Technology change introduces a significant — and often overlooked — cost.

Most organisations replace or upgrade core systems every 5–10 years, including:

• ERP migrations or version changes
• Ecommerce replatforming
• New marketplaces and sales channels

When systems change, custom integrations frequently become partially or fully obsolete. At that point, the original investment must be written off and rebuilt — effectively paying for the integration twice.

This pattern is consistently observed in ERP integrations involving Sage, Acumatica, Syspro and SAP Business One within multi-channel ecommerce environments.

Build vs Buy: A Cost Comparison Over Time

The Stock2Shop Alternative: Paying for Outcomes, Not Code

Stock2Shop’s monthly fee model converts a wide range of unpredictable, long-term integration costs into a known, manageable operating expense.

What the Monthly Fee Covers

• Pre-built, battle-tested ERP and ecommerce integrations
• Continuous platform updates and compatibility management
• Monitoring, error handling and operational support
• Scalability as transaction volumes grow
• Deep integration expertise across ERPs, retailers and ecommerce platforms

Instead of owning fragile custom code, businesses gain access to an integration layer that evolves alongside the ecosystem.

Reduced Risk, Greater Flexibility

By avoiding heavy upfront capital investment, organisations:

• Reduce financial risk
• Avoid technical lock-in
• Remain agile as systems, channels and strategies change

When an ERP or ecommerce platform changes, the integration adapts without requiring a full rebuild or write-off.

A Shift in Mindset: Capex vs Total Cost of Ownership

The real comparison is not:

Once-off build cost vs monthly fee

It is:

Total cost of ownership over 3–5 years

When maintenance, staffing risk, opportunity cost, scalability and system change are considered, many organisations find that a managed integration platform is simpler, more resilient and more economical.

Key Takeaways

• Building custom integrations introduces long-term maintenance and staffing costs that are rarely budgeted upfront.
• Custom integration code is highly sensitive to ERP, ecommerce and API changes.
• Opportunity cost for internal IT teams often exceeds the original development cost over time.
• Managed integration platforms reduce operational risk and improve scalability.
• Over a 3–5 year horizon, predictable operating costs frequently outperform capital-heavy build approaches.

In a technology landscape defined by constant change, flexibility and sustainability matter more than owning integration code outright.

If you’re weighing the real cost of building versus buying, contact Stock2Shop to find out how we can help you model the long-term financial and operational impact before you commit — using your real systems, volumes and growth plans.

FAQ